\documentclass[12pt]{book}
\usepackage{geometry}                % See geometry.pdf to learn the layout options. There are lots.
\geometry{letterpaper}                   % ... or a4paper or a5paper or ... 
\usepackage{graphicx}
\usepackage{amssymb}

\usepackage{fontspec,xltxtra,xunicode}
\defaultfontfeatures{Mapping=tex-text}
\setromanfont[Mapping=tex-text]{Hoefler Text}
\setsansfont[Scale=MatchLowercase,Mapping=tex-text]{Gill Sans}
\setmonofont[Scale=MatchLowercase]{Andale Mono}

\title{Brief Article}
\author{The Author}

\begin{document}
 \newfontfamily{\H}{Hei}
 \newfontfamily{\S}{宋体}
 \newfontfamily{\F}{仿宋_GB2312}
 \newfontfamily{\K}{Kai}
 \newfontfamily{\Y}[Scale=1.5]{微软雅黑}
 \newfontfamily{\X}[Scale=3.5]{方正静蕾简体}
{\X 徐静蕾的字体还是比较秀气\\
春风吹\\
战鼓雷\\想淡淡得的身份是收是否\\
}\\
{\Y 这是微软雅黑字体，看着还是相当不错得吧} \\ 
{\H 这是黑体的中文字体}\\
{\K 这是楷体}\\
{\F 这是仿宋体}\\
{\S 这是宋体}
\end{document}  